Toner compositions with color pigments are known. For example, U.S. Pat. No. 4,948,686 discloses processes for the formation of two color images with a color developer comprised of a first toner comprised of certain resin particles, such as styrene butadyene, and a first pigment such as copper phthalocyanine.
Toners with metal-containing pigments have difficulty meeting strict regulations that are prescribed for disposal of hazardous materials. Jurisdictions such as California impose strict regulations on the disposal of metal-containing materials. The regulations apply to xerographic toners.
It is desirable to lower the amount of metal in toners to meet hazardous disposal standards. However, lowering metal content can adversely affect properties of the toners such as light fastness, electrical properties and bleed resistance. Meeting hazardous disposal standards is particularly a problem with compositions that provide blue, cyan, red, magenta and green colorations for high performance xerographic toners.
The present invention provides a toner composition having a lower total amount of toxic metal content. The composition is characterized by excellent electrical properties for use as a high performance xerographic toner. The composition of the invention has excellent light fastness, electrical properties and bleed resistance. The properties by the present toner compositions are favorably comparable to properties for similar toner compositions which contain toxic materials, but the present toner compositions are substantially reduced in toxic material content.
U.S. Pat. No. 4,051,052 to Ueda et al. discloses various types of dyes or pigments that are used in liquid developers.
U.S. Pat. No. 3,669,922 to Bartsch et al., U.S. Pat. No. 4,655,001 to Fujii et al., U.S. Pat. No. 4,711,832 to Gruenbaum, et al., U.S. Pat. No. 4,948,686 to Koch et al. and U.S. Pat. No. 5,166,027 to Machida et al. disclose toners containing combinations of pigments.
Fujii et al., U.S. Pat. No. 4,665,001 relates to toner compositions wherein one preferred embodiment comprises a halogen-substituted copper phthalocyanine pigment and an indanthrone pigment used as a combination.